Pumping system



Dec. 27, 1966 c. o. MEYERS ETAL 3,294,024

PUMPING SYSTEM 5 Sheets-Sheet 1 Filed June 10, 1964 INVENTORS. CHARLESO. MEYERS MAURICE 5. H055 BY KL/ ATTORNEY Dec. 27, 1966 c. o. MEYERSETAL. 3,294,024

PUMPING SYSTEM 5 Sheets-Sheet 2 Filed June 10, 1964 INVENTORS. CHARLESO. MEYERS BY MAURICE 5. :2

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A T TORNE Y 1965 c. o. MEYERS ETAL 3,294,024

PUMPING SYSTEM 5 Sheets-Sheet 5 Filed June 10, 1964 INVENTORS. CHARLES0. MEYERS MAURICE 5. H055 BY ATTORNEY United States Patent 3,294,024PUMPING SYSTEM Charles 0. Meyers and Maurice S. Hoss, Tulsa, Okla.,assiguors to Combustion Engineering, Inc., New York County, N.Y., acorporation of Delaware Filed June 10, 1964, Ser. No. 373,929 2 Claims.(Cl. 103--21) available for producing water from deep subterraneansands. However, the control of pumping has not been developed toproperly protect the pumping equipment, conserve the available water orproduce most efiiciently from a minimum supply.

The centrifugal type pumps in common use will be damaged if allowed torun dry. Therefore, it is important that a water well be produced as toguard against lowering the well level to the point of withdrawal by thepump. At the same time the pump is controlled so it will not run dry,the pump operation must be carried out so as to account for a watertable relatively high with respect to the depth of the well andrelatively low with respect to well depth. I

A principal object of the invention is to supply water to a varyingdemand at a predetermined maximum pressure.

Another object is to supply water at a predetermined maximum rate, whenthe water table is relatively high, while maintaining a predeterminedlevel in the reservoir of the well bore.

Another object is to produce Water from a well, when the water table isrelatively low, at the maximum capacity of the well reservoir withoutrunning the pump dry.

The present invention contemplates completing a well bore deep enough toprovide a reservoir of water in the bore. A power source is then mountedat the top of the bore and connected to pump elements within the bore towithdraw water from the reservoir. The pumping is then controlled undertwo general conditions. First, when the water table is relatively highwith respect to the depth of the Well bore, the pumping is carried outto withdraw water so as to maintain a predetermined maximum outputpressure. Second, when the water table is relatively low with respect tothe depth of the well bore, the pumping is carried out to withdraw waterso as to maintain a reservoir level as low as practical without loweringthe level to the point of withdrawal.

To control the pumping of the Water from the well reservoir, arestrictive element in the output of the pump is positioned by a controlsystem responsive to level detector devices suspended in the well bore.The control system operates the control element in three different ways.First, the control element is opened at a predetermined rate when thereservoir level is above the level detectors. Second, the controlelement is closed at a predetermined rate when the reservoir level isbelow the level detectors. Third, the control element is held in theposition attained when the level has been moved to between the leveldetectors. As the third position of the control element is a combinationof the times within which the control element is being opened andclosed, the position of the element when the level is between thedetectors is established to balance the rate of supply of water into thebore from the water table in supplying the demand for water.

Other objects, advantages and features of this invention will becomeapparent to one skilled in the art upon consideration of the writtenspecification, appended claims and attached drawings, wherein;

FIG. 1 is a diagrammatic representation of a water well extending to adepth well below the water table and equipped with pumping equipment inwhich the present invention is embodied;

FIG. 2 is similar to FIG. 1 but with the water table indicated asrelatively low with respect to the bottom of the well; and

FIG. 3 is a schematic illustration of the circuit between the leveldetectors and the control valve motor windings.

General arrangement of apparatus Referring to FIGS. 1 and 2, we haveshown a well shaft 1 sunk from the ground surface 2 to a distance belowa subterranean water sand 3. The sand 3 stratum may vary in depth. Onevariation is indicated, the sand rising to some distance indicated at 4.

The shaft I normally has a casing 5 which is perforated at 6 to letwater flow readily from sand stratum 3 into the shaft 1. It is expectedthat the water will flow through perforations 6 from a level above thetop of sand 3 at 7 or from level 8 which is below the top of sand 3.

During the rainy season of the year, the general water table is expectedto be relatively high with respect to the bottom of the well shaft 1.The exact height, or depth of the water table from surface 2, willdepend upon the water flowing into the area generally. We havearbitrarily placed line 7 as an indication of this height.

When water is plentiful, i.e., the Water table level is at 7, theproblem of pumping is simply one of supplying the demand at apredetermined maximum pressure. The problem becomes more complex whenthe scarcity of water lowers the water table. Line 8 has beenestablished to represent this height. Then the withdrawal of water fromthe well reservoir becomes an art in keeping as low a well level, withinshaft 1, as possible without lowering the level to the intake end of thepump. The pump must not run dry but as high a gradient as practical mustbe maintained between 8 and the well level. Both methods of operationare carried out by the proper control of pump 9 which is mounted on theend of column pipe 11.

Column pipe 11 is suspended from some type of base at the surface 2. Wehave illustrated a simple concrete slab 12 which is formed over andbeyond casing 5. A motor housing 13 is mounted on a base member which ismounted on the top of slab 12. The base member supports pipe 11 in shaft1 from the upper end 14 of pipe 11. Shaft 15 mechanically connects thepump motor within housing 13 to the several stages of blades within pump9.

The water withdrawn from the reservoir in casing 5 is forced up columnpipe 11, through base member 16 and out conduit 17 for use. Mounted inoutput conduit 17 is a valve 18 which is positioned to develop a backpressure on the pump output in control of the Withdrawal from thereservoir in shaft 1. Valve 18 is positioned by an electric motor 19,the motor 19 being controlled by a circuit Within the unit 20.

Probe 21 and probe 22 are suspended in the well shaft 1, and are locatedspecifically between column pipe 11 and easing 5. No specificarrangement has been illustrated for suspending probes 21, 22 in theWell shaft or for adjusting their vertical positions independentlywithin the shaft. Various mechanical arrangements for supporting andadjusting the probes can be made. The basic disclosure of the inventionis furthered by developing that these probes are of the conductance typeand by such characteristic transmit distinguishing signals to unit 20when the level of water is above the probes, between the probes andbelow the probes.

Electrical power sources for the motor within housing 13 and the systemWithin unit 20 are indicated. Such electrical power is now generallyavailable even in remote locations throughout the United States wherewells of this type are located.

Operation The pump is desirably a constant speed, centrifugal, type.Therefore, the rate of water withdrawn is established by the setting ofvalve 18 by motor 19 to maintain 5 back-pressure on the pump.

The general system of control is arranged to maintain the setting ofvalve 18 for as long as thelevel of the reservoir is between the probes21, 22. If the, level goes above the upper probe 21 the valve 18 startsopening. If the level then drops below probe 21 thenew opening of valve18 is maintained. If the level continues to fall and drops below probe22, the valve 18 starts toclose. If the level then rises to probe 22 thevalve 18 opening is maintained. Eventually, with these actions on valve18, a position will be found for valve 18 which will keep the well levelbetween the probes 21, 22. The flow into vthe well reservoir will thenbe balanced against the flow out of conduit 17.

Downstream demand for the water of circuit 17 may change. Then the valve18 will have to be readjusted to the change in pressure drop .across thevalve. If the demand is too'great for the available in-flow of waterinto the well reservoir, the well level will sink below the probe 22 andvalve 18 will close, opening only as the well level rises above probe21. If the well supply is greater than the demand, the valve 18 willopen as the well level goes above probe 21, closing only when the welllevel sinks below probe 22.

FIG. 1 is arranged to show the condition of operation when the watertable is high, i.e., the level 7 is well above the bottom of shaft 1.Probes 21 and 22 are shown with the well reservoir level between them.Valve 18 is set to permit withdrawal of water through conduit 17 at arate to match the flow of water through perforakeeping the reservoirlevel above probe 22, the probe 21 will open the valve 18 when thereservoir level rises above probe 21.

FIG. 3 shown the basic circuit for controlling motor 19 by probes 21,22. Unit 20 of FIGS. 1 and 2 is illustrated as oriented to the windingsof motor 19 and probes 21, 22. It was previously indicated that probes21, 22 were of the conductance type. In FIG. 3, their cooperation withthe circuit of unit 20, to controlmotor 19, is

shown in sufficient detail for the purpose of disclosing the presentinvention.

The basic purpose of unit 20 is to connect a power supply 30 (220 v.) towinding 31 or winding 32. Winding 31 will turn motor 19 to close Valve18 when energized. Winding 32 will open valve 18 when energized.

The circuit within unit 20 responds to probes 21, 22 to selectivelyenergize the motor windings.

The circuit of unit 20 is shown in, its condition when the water levelin the well shaft 1 is below probe 22.

Switch arm 33 is making contact with 34,- connecting winding 31 withsource 30; so energized, motor 19 is rotating to close valve 18 andthereby permit the water flowing into the well shaft to rise.

The position of arm 33 is controlled by coil 35. When coil 35 isenergized, arm 33 is pulled downinto'engagement with contact 36. Coil 35is in circuit with the plate and grid of tube 37. The tube 37 is agas-filled tube which conducts when the grid voltage is reduced to apredetermined value.

A transformer 38 is supplied from a source 39 v.). Secondary winding 40is in series with coil 35 and when tube 37 is allowed to conduct, coil35 is energized to pull down arm 33. Secondary winding 41 has a portionof its output voltage applied to the grid of tube 37 to keep the tube 37from conducting.

All that is necessary to reduce the grid voltage of tube 37 enough tofire tube 37 is to connect the grid to ground; this is done throughprobe 22. When the water of the well raises toprobe 22 the grid isgrounded, tube 37 conducts and coil 35 is energized. Valve 18 is held inthe position it had when the water level reached probe 22 anddisconnected winding 31 from source 30. i

Switch arm 33 is pulled down to contact arm 36, thereby connectingsource 30 to switch arm 42. The water level is between the two probes.Both windings of the motor 19 are cle-energized untilthe water levelreaches upper probe 21 or falls below probe 22.

Tube .43 controls coil 44 in the same manner as tube 37 controlled coil35. Source 45 supplies a transformer which supplies power for coil 44and a grid voltage for tube 43. Contact of probe 21 with the waterconnects the grid to ground and permits the .tube to conduct. Coil 44 isenergized and arm 42 is pulled down into contact with 46. Motor winding32 is thereby connected to source 30 and valve 18 is moved toward itsopen position until probe 21 is uncovered.

The operation of the valve 18 by probes 21, 22 is now completelydescribed. The water between the probes fixes the valve positionwherever it was when the level came between the probes. If the levelsinks below the lower probe the valve closes; if the level rises abovethe upper probe the valve opens. When the level is between theprobes,the valve does not move. The output from the well is therebycontrolled by a search for the valve position which will balance theinflow to the well reservoir with the water drawn from conduit 17.

With the unit 20 responding to probes as disclosed,

the positioning of the probeswithin the well bore will carry out theobjects of the invention.

- From the foregoing it will be seen that this invention is one welladapted to attain all of the ends and objects hereinabove set forth,together with other advantages which are obvious and which are inherentto the method and apparatus.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

As many possible embodiments may be made of the invention withoutdeparting from the scope thereof, it is to be understood that all matterherein set forth or shown in the accompanying drawings is to beinterpreted as illustrative and not in a limiting sense.

The present invention having been described, what is claimed is: I

1. A system with which to produce a water wall, in.- cluding,

a wellbore extended from the ground surface to form a reservoir of waterin the bottom of the bore,

a column pipe extending from the ground surface and within the bore to a.point near the bottom of the bore, Y r

pump elements mounted within the pump shaft so as to draw water from thereservoir and up the column pipe to the ground surface,

means for powering the pump elements connected to the pump elements,

a valve mounted in the pump discharge,

first and second level detection elements spaced vertically in the wellbore,

and an electrical circuit connected to the level detec tion elemQ ltS.and the valveto control the setting of the valve in accordance with theposition of the water level in the well bore with respect to the leveldetection elements,

whereby the valve will be moved toward full open as long as the waterlevel is above both elements, the valve will be held at the settingreached as the water level is brought to between the elements and thevalve will be moved toward full closed as long as the water level isbelow both elements.

2. A system for transfer of liquid from a source to point of deposit,including,

a source of liquid,

a receptacle for liquid from the source,

a conduit connecting the source and receptacle,

a pump connected to the conduit for moving the liquid from the sourcethrough the conduit to the receptacle,

a valve mounted in the conduit,

first and second level detection elements spaced vertically with respectto a level of the liquid,

and an electrical circuit connected to the level detection elements andthe valve to control the valve setting,

References tCited by the Examiner UNITED STATES PATENTS Kingsbury137-392 Kirgan 103-97 Fillo 137-392 Buck 103-25 Arndt 103-25 McDaniel103-25 Kusner 1034O Rudy et al. 103-25 20 MARK NEWMAN, Primary Examiner.W. J. KRAUSS, Assistant Examiner.

1. A SYSTEM WITH WHICH TO PRODUCE A WATER WALL, INCLUDING, A WELL BOREEXTENDED FORM THE GROUND SURFACE TO FORM A RESERVOIR OF WATER IN THEBOTTOM OF THE BORE, A COLUMN PIPE EXTENDING FROM THE GROUND SURFACE ANDWITHIN THE BORE TO A POINT NEAR THE BOTTOM OF THE BORE, PUMP ELEMENTSMOUNTED WITHIN THE PUMP SHAFT SO AS TO DRAW WATER FROM THE RESERVOIR ANDUP THE COLUMN PIPE TO THE GROUND SURFACE, MEANS FOR POWERING THE PUMPELEMENTS CONNECTED TO THE PUMP ELEMENTS, A VALVE MOUNTED IN THE PUMPDISCHARGE, FIRST AND SECOND LEVEL DETECTION ELEMENTS SPACED VERTICALLYIN THE WELL BORE, AND AN ELECTRICAL CIRCUIT CONNECTED TO THE LEVELDETECTION ELEMENTS AND THE VALVE TO CONTROL THE SETTING OF THE VALVE INACCORDANCE WITH THE POSITION OF THE WATER LEVEL IN THE WELL BORE WITHRESPECT TO THE LEVEL DETECTION ELEMENTS, WHEREBY THE VALVE WILL BE MOVEDTOWARD FULL OPEN AS LONG AS THE WATER LEVEL IS ABOVE BOTH ELEMENTS, THEVALVE WILL BE HELD AT THE SETTING REACHED AS THE WATER LEVEL IS BROUGHTTO BETWEEN THE ELEMENTS AND THE VALVE WILL BE MOVED TOWARD FULL CLOSEDAS LONG AS THE WATER LEVEL IS BELOW BOTH ELEMENTS.